Tracking Thermal Glow: Infrared Imaging Astronomy Quiz

If all objects with a temperature above absolute zero emit electromagnetic radiation, and if cooler objects like planets emit most of their energy at longer wavelengths, then sensors tuned to the infrared spectrum can detect that energy as heat.

If there is an inverse relationship between temperature and wavelength, and if infrared light has a longer wavelength than visible light, then a cooler object like a planet will peak in the infrared rather than the visible spectrum.

If the electromagnetic spectrum is ordered by energy, and if infrared radiation has lower energy than visible light, then the wave physics dictate that infrared must have a longer wavelength.

If a planet has recently formed, it retains significant thermal energy from its formation process; if it is hot, it glows brightly in the infrared, making it easier to distinguish from the host star's glare.

If infrared light can penetrate dust clouds and detect low-temperature thermal signatures, then it is the ideal tool for seeing forming stars, cool substellar objects, and specific chemical molecules in atmospheres.

If the telescope itself is warm, it will emit its own infrared radiation; if the sensors are trying to detect faint heat from a distant planet, then the telescope's own thermal "noise" must be minimized by cooling the instruments to near absolute zero.

If water vapor and carbon dioxide are highly efficient at absorbing infrared radiation (the greenhouse effect), then Earth's atmosphere acts as a filter that blocks most infrared light from reaching ground-based telescopes.

If gold is one of the most efficient reflectors of infrared radiation across a wide range of wavelengths, then coating the mirror in a thin layer of gold maximizes the number of infrared photons sent to the detectors.

If a star is 10^9 times brighter than a planet in visible light, but only 10^6 times brighter in the infrared, then the contrast gap is reduced by 1,000 times, making the planet much easier to resolve.

If heat comes from the Sun and the telescope's electronics, then a sunshield blocks solar radiation, liquid coolants absorb internal heat, and a distant orbit at L2 keeps the craft away from Earth's thermal glow.

If visible light waves are small enough to be scattered by dust particles (Mie scattering), and if infrared waves are larger than those particles, then the infrared light can pass through the clouds without being diverted.

If a brown dwarf lacks the mass to trigger hydrogen fusion, it will not glow brightly in visible light; however, if it still retains heat from its initial collapse, it will be visible to sensitive infrared detectors.

If the spectrum is sorted by increasing wavelength, it proceeds from visible to infrared, then to microwave, and finally to radio waves; thus, infrared sits between visible and the radio/microwave region.

If the peak wavelength of a blackbody curve is determined by temperature (Wien's Law), then measuring which specific infrared wavelength is the brightest allows astronomers to calculate the temperature of the planet's surface or atmosphere.

If these specific molecules absorb and emit energy at known infrared frequencies due to their molecular bonds, then their presence in an exoplanet's atmosphere will create distinct patterns in the infrared spectrum.

If the Sun is a massive source of infrared radiation and is physically opaque, then no telescope—infrared or otherwise—can see through its core to objects on the other side.

If the standard unit for mid-to-long infrared light is the micrometer (10^-6 meters), then the common term used by astronomers for this unit is the micron.

If the diffraction limit of a telescope is proportional to (wavelength / diameter), and if infrared light has a longer wavelength than visible light, then an infrared telescope needs a much larger aperture to produce an image as sharp as a visible light telescope.

If the Earth's atmosphere absorbs infrared light and emits its own heat (noise), then space provides a cold, transparent environment that allows for the high-sensitivity measurements required to find small, faint worlds.

If stars form from collapsing clouds, and if the remaining material flattens into a disk due to conservation of angular momentum, then the friction and radiation in this disk create heat that is perfectly captured by infrared sensors.